Copy of INCOME TAX RETURN FROM LONDON Not Yet received at Bhubaneswar

A LETTER FROM ROYAL MAIL WAS SENT ON 3/10/2019 at 11.59 PM!IT LEFT UK AT 1.44 AM on Friday the 4/10/2019 the item was received at Delhi International Mail Centre,India on 7/10/2019 at 8.01 AM.On tracking the mail Ref No :RU852145444GB ADDRESSED TO ME RAMESH CHANDRA DAS,D-304,LIFESTYLE GREEN APARTMENT,PATIA,BHUBANESWAR-751024 it is seen that it’s lying with the CUSTOMS IN THE DESTINATION COUNTRY IE Kolkata AIR FOREIGN RLO ,BUILDING AS ON 11/10/2019.Then on 15/10/2019 it was released from Customs India and item has left the Overseas International Processing Centre ,Kolkata,Air Foreign RLO ,BUILDING ,INDIA AT 11.26 am.

Since this is a simple letter,I really wonder why it should go to Kolkata,when it has reached Delhi,the country’s Capital.From Delhi why could it not been sent to Bhubaneswar as its letter only.